In wireless communication system, data transmission services can be mainly classified into a multicast/broadcast service and a unicast service.
The unicast service is a sort of a point-to-point service for transmitting data to a single receiver from a single source. According to the unicast service, different data are transmitted to different receivers or receiver groups on different radio resources, respectively.
The multicast/broadcast service (hereinafter abbreviated MBS) is a sort of a point-to-multipoint service for transmitting data to a plurality of receivers from a single source. According to the MBS, the same data is transmitted to a plurality of receivers on a common radio channel for efficient use of radio resources.
In a general wireless access system, MBS may be mainly categorized into two types. In particular, a 1st type corresponds to a single base station (single-BS) access. According to the single-B access, a service is provided by a single base station within a single cell. A 2nd type corresponds to a multiple base station access (multi-BS access). According to the multi-BS access, several base stations configure a single MBS zone to provide MBS contents. Namely, an MBS service is provided in a manner that the same burst is allocated from an MBS server in a plurality of cells within the same MBS zone using a single MBS zone identifier (ID). Hence, in case of a BS included inter-cell movement, it may be able to obtain service continuity and macro-diversity gain without handover.
Meanwhile, for the variety and efficiency of a wireless communication service, it may be necessary to allow base stations belonging to different MBS zones to simultaneously transmit MBS data. And, it may be also necessary to allow a base station to simultaneously transmit MBS data and unicast data both. In particular, data having different properties or data of different types need to be transmitted in a manner of being multiplexed together. To this end, the demand for an efficient resource allocation method for transmitting MBS data in at least two MBS zones or both MBS data and unicast data is rising. Moreover, in order for a user equipment to receive data of different properties/types transmitted in a manner of being multiplexed together, the user equipment should be provided with allocation information on an MBS data carried resource per MBS zone and allocation information on a unicast data carried resource.